B. Paassen, B. Hammer, T. Price, T. Barnes, S. Gross, and N. Pinkwart. The Continuous Hint Factory - Providing Hints in Vast and Sparsely Populated Edit Distance Spaces. Journal of Educational Data Mining, Educational Data Mining Society, volume 10, issue 1, 2018. T. Barnes, K. Boyer, S. I.-H. Hsiao, N. T. Le, and S. Sosnovsky. (Eds.). International Journal of Artificial Intelligence in Education, Special Issue on AI-supported Education for Computer Science, Springer Verlag, volume 27, issue 1, 2017.